1. Field of the Invention
The present invention relates to a clip that is attachable to a metal panel to which a vehicle battery pack or other such devices is secured. More particularly, the present invention relates to a clip having an anchor portion that is capable of being inserted into a nut (a weld nut) welded to a metal panel and is capable of engaging a female thread formed in the nut.
2. Description of Related Art
This type of clip is already known and is taught, for example, by Japanese Laid-Open Patent Publication No. 11-093923. The clip includes an anchor portion (an engagement stem portion) that is capable of being inserted into a nut welded to a metal panel, and a plurality of blade-shaped ribs formed in an outer surface of the anchor portion. The ribs are vertically sequentially arranged in four rows along an axis of the anchor portion. The ribs are diagonally projected outwardly toward a proximal end of the anchor portion, so that the anchor portion can have a tree-shape as a whole.
The nut is welded to the metal panel while aligned with a through hole formed in the metal panel. Therefore, when the anchor portion of the clip is inserted into the through hole, the anchor portion can be inserted into the nut via the through hole. Upon insertion of the anchor portion into the nut, the ribs of the anchor portion can move within a female thread formed in the nut while elastically flexed, so that all of or a part of the ribs can engage the female thread of the nut. As a result, the clip can be attached to the metal panel via the anchor portion.
However, according to the clip in which the ribs are arranged along the axis of the anchor portion, when the anchor is inserted into the nut, a large insertion load (insertion resistance) can be produced. To the contrary, when the anchor is applied with a load in a direction in which the anchor is pulled out of the nut, the ribs can be easily elastically (reversely) flexed, so that the anchor can be easily pulled out of the nut.
Generally, there are two different types of nuts that are the same in inner diameter thereof and different from each other in thread pitch of female thread formed in the nuts. For example, the nut classified as “B 0205” of JIS (Japanese Industrial Standards) code has an inner diameter of 10 mm and a thread pitch of 1.25 mm. Conversely, the nut classified as “B 0207” of JIS code has an inner diameter of 10 mm and a thread pitch of 1.50 mm. Therefore, when the metal panel has the different types of nuts that are different from each other in thread pitch of the female thread formed in the nuts, different types of clips adaptable to such nuts must be manufactured and selectively used. This may lead to increased manufacturing costs. Further, working efficiency of the clip insertion operation can be reduced. Thus, there is a need in the art for improved clips.